1. Field of the Invention
This invention relates to a fixing and combining device for the brake disc of a remote-controlled model car, particularly to one having the brake disc formed integral with plural combining projections at the annular edge of its center hole to be tightly fixed between the engage notches of a combining cup and a transmission rod, able to enhance the strength of the brake disc combined.
2. Description of the Prior Art
Referring to FIGS. 1 and 2, the brake device of a conventional remote-controlled model car 10 is composed of a combining cup 11, a movable brake plate 12, a brake disc 13 and a fixed brake plate 14. The combining cup 11 has its front side provided with a transmission shaft 111, and the brake disc 13 is bored with a center hole 131 having the same shape as that of the outer periphery of the combining cup 11 for the combining cup 11 to be inserted therethrough so as to combine the brake disc 13 together with the combining cup 11 in a tight way. In addition, the brake disc 13 is clamped between the movable brake plate 12 and the fixed brake plate 14. Thus, when the movable brake plate 12 and the fixed brake plate 14 mutually carry out clamping motion, a friction resistance will be produced to let the brake disc 13 and the transmission shaft 111 stop rotating and brake the remote-controlled model car.
However, referring to FIG. 3, the combining cup 11 of the conventional remote-controlled model car 10 is tightly engaged with the inner edge of the center hole 131 of the brake disc 13 and actuated by the brake disc 13 to stop rotating, and both the combining cup 11 and the brake disc 13 are made of metal. Therefore, due to being tightly engaged with the combining cup 11, the combining portion 132 of the inner edge of the center hole 131 of the brake disc 13 is likely to be easily worn off and produce a gap. As a result, the combining cup 11 and the brake disc 13 are unable to be kept tightly fitted together, rendering the brake disc 13 liable to fall off. Under the circumstances, when the remote-controlled model car is running, the brake disc 13 is easy to vibrate to make noises, and when the running remote-controlled model car is to be braked, it may result in virtual work owing to the gap between the brake disc 13 and the combining cup 11, thus impossible to quickly brake the remote-controlled model car and likely to lower braking efficacy.